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91.
A 60‐day feeding trial was conducted to quantify the effects of microbial phytase supplementation on apparent absorption, whole body and bone contents of minerals in Pangasius pangasius fingerlings. Seven isoprotein (35.67%) and isocaloric (3870 kcal kg?1) diets were prepared with graded levels of supplemental phytase at 0 (T1), 150 (T2), 250 (T3), 350 (T4), 500 (T5), 1000 (T6) and 2000 (T7) FTU (Phytase Units) kg?1. Three hundred and fifteen fingerlings of P. pangasius (1.97–2.05 g) were randomly distributed in seven treatments with three replicates each. There was significant increase (P<0.05) in tissue protein content in phytase‐supplemented groups compared with the control. Apparent absorptions of calcium (Ca), phosphorus (P), magnesium (Mg), manganese (Mn), zinc (Zn), iron (Fe), potassium (K), copper (Cu) and cobalt (Co) were significantly (P<0.05) higher in the phytase‐supplemented groups than the control group. Faecal ash and P contents were significantly (P<0.05) higher in the control (T1) than the phytase‐supplemented groups. Whole‐body contents of Ca, P, Zn, Fe, Cu and Co were significantly (P<0.05) improved by the dietary supplementation of phytase‐barring Mg and Mn. Concentrations of bone Ca, P, K, Cu and Co were significantly (P<0.05) higher in phytase‐supplemented groups. Bone ash contents (40.77–44.85%) were increased concomitantly with the increased level of phytase inclusion upto 500 FTU kg?1 diet. It was observed that a minimum dose of 250 FTU phytase kg?1 diet improved the mineral absorption and utilization in P. pangasius fingerlings.  相似文献   
92.
We examined the effects of intercropping with Acacia senegal (L.) Willd on growth and yield of sorghum (Sorghum bicolor L.), sesame (Sesamum indicum L.) and roselle (Hibiscus sabdariffa). Field experiments were conducted in El-Obeid Research farm (13°10’ N; 30°12’ E), North Kordofan State, Sudan, during 2002 2003 in an 11-year-old A. senegal plantation. The experimental design was randomized complete block design (RCBD) with four replications. Data were recorded for plant height (cm), fresh weight (kg ha -1 ), dry weight (kg ha -1 ), crop yield (kg ha -1 ), and gum yield (kg ha -1 ). We used Land Equivalent Ratios (LER) and simple financial analyses of gross surpluses to evaluate the productivity and profitability of the different treatments. The results indicated that A. senegal trees had a beneficial effect on crop performance and yield as well as gum yield. Significant differences (p<0.05) were obtained for plant height, fresh weight, dry weight and crop yield. Therefore, yield of sorghum, sesame and roselle under intercropping system were 13.7%, 23.8% and 20.9% higher than that obtained in the sole cropping system respectively. The highest yield increase was observed with sesame (23.8%). Gum yield (g/tree/picking) was signifi- cantly (p<0.05) increased for sorghum, sesame and roslle under inter-cropping system. The highest yield of (298g/tree/picking) was obtained when roselle was intercropped with A. senegal, while the least gum yield of (239 g tree-1 ) was recorded in pure A. senegal plot. All the treatments gave land equivalent ratio (LER) of more than one-indicating the superiority of growing the field crops in intercropping over the sole cropping systems. The highest LER of 3.8 was obtained for sesame intercropped with A. senegal (Hashab), followed by 3.7, when sorghum was intercropped with A. senegal and 3.3 when roselle intercropped with A. senegal. All the treatments gave positive net revenues, the highest being for intercropped sorghum (558 SDG ha -1 ) (SDG=Sudanese gienh). The intercropping of roselle gave the second net revenue (518 SDG ha -1 ),while the sole sorghum gave the lowest net revenue (501 SDG ha -1 ).  相似文献   
93.
Climate change is likely to affect the persistence of large, space-requiring species through habitat shifts, loss, and fragmentation. Anthropogenic land and resource use changes related to climate change can also impact the survival of wildlife. Thus, climate change has to be integrated into biodiversity conservation plans. We developed a hybrid approach to climate-adaptive conservation landscape planning for snow leopards in the Himalayan Mountains. We first mapped current snow leopard habitat using a mechanistic approach that incorporated field-based data, and then combined it with a climate impact model using a correlative approach. For the latter, we used statistical methods to test hypotheses about climatic drivers of treeline in the Himalaya and its potential response to climate change under three IPCC greenhouse gas emissions scenarios. We then assessed how change in treeline might affect the distribution of snow leopard habitat. Results indicate that about 30% of snow leopard habitat in the Himalaya may be lost due to a shifting treeline and consequent shrinking of the alpine zone, mostly along the southern edge of the range and in river valleys. But, a considerable amount of snow leopard habitat and linkages are likely to remain resilient to climate change, and these should be secured. This is because, as the area of snow leopard habitat fragments and shrinks, threats such as livestock grazing, retaliatory killing, and medicinal plant collection can intensify. We propose this approach for landscape conservation planning for other species with extensive spatial requirements that can also be umbrella species for overall biodiversity.  相似文献   
94.
European Journal of Plant Pathology - Virus-induced gene silencing (VIGS) is a reverse genetic tool used to identify the function of individual genes by reducing their expression. Here VIGS was...  相似文献   
95.
96.
Instrumental light aging is one of the most important tools for restoration and conservation of historical textiles. It used in testing stability of conservation materials, in addition to its lightening effect during the presentation in the museums. Light fading is an important tool for preparing the aged textile and other polymeric samples especially for archaeological conservation applications. Many fadometers do not give homogeneous exposure for all sample’s areas. This work studies the color changes of silk fabric dyed with turmeric (Curcuma longa L.) mordanted with alum or ferric sulfate. Color change was studied for the exposure periods ranged from five to hundred hours. Three positions of different irradiance levels were measured on the same sample namely (bottom, middle and upper). Individual color change for each position was recorded and studied. The results showed that there is non-homogeneous irradiance distribution due to different positions in fadometer or mordant used.  相似文献   
97.
98.
In the present study, 48 crossbred does (Nubian × Baladi) were used to investigate physiological (mucus and hormonal) traits as affected by gestation pattern (pre‐, full‐ and post‐term parturitions). The incidence of full‐term (does with a gestation length of 146–152 days) was the highest (54.5%), followed by pre‐term (does with a gestation length of 140–145 days; 36.9%) and post‐term (does with a gestation length of 153 days; 8.9%), respectively. Prediction of gestation pattern by using some body measurements was also studied. Cervical mucus samples were collected during estrus to determine spinnbarkeit (i.e. strength, viscosity or stretchability) and pH values of the mucus. Mucus was also collected pre‐parturition daily from day 140 of gestation until delivery, to evaluate the ferning arborization. Blood samples were collected on the day before mating (0 time), 1 (at mating), 30, 60, 90 and 145 days after mating. The results showed that spinnbarkeit and pH in cervical mucus at estrus, serum estradiol‐17α (E2) at day 5 before delivery, and progesterone (P4) levels differed insignificantly according to gestation pattern. The fern degree between day 140 of gestation and day of delivery was the highest in pre‐term does, while it was the lowest in post‐ and full‐term does. The gestation length was the highest in post‐term does (157.5 days), and the lowest in pre‐term does (141.5 days). During winter, the incidence of pre‐term deliveries was the highest (54.5%), but in spring, full‐term deliveries were the most common (58.3%). Most of the traits studied were insignificantly affected by season of birth. Post‐term delivery can be estimated by doe weight and wither height, while full‐term delivery can be anticipated using by hip height and abdomen girth. Pre‐term does can be detected by cervical mucus fern between day 140 of gestation and day of delivery. Post‐term does can be defined by doe weight and wither height, while full‐term deliveries can be defined by hip height and abdomen girth, during pregnancy.  相似文献   
99.
Values for pharmacokinetic variables are usually obtained in healthy animals, whereas drugs are frequently administered to diseased animals. This study investigated cefquinome pharmacokinetics in healthy goats and goats with experimentally induced mastitis. Five adult lactating goats received 75 mg of cefquinome intramammary infusion using a commercially available product into one udder half in healthy goats and goats with clinical mastitis that was induced by intracisternal infusion of 100 cfu of Staphylococcus aureus ATCC 29213 suspended in 5 ml of sterile culture broth. Cefquinome concentrations were determined in plasma and skimmed milk samples using high‐performance liquid chromatography (HPLC). Pharmacodynamics was investigated using the California Mastitis Test and pH of milk. Experimentally induced mastitis significantly increased the California Mastitis Test score and pH, and decreased the maximal cefquinome concentration and shortened the half‐life in milk when compared to healthy goats. In conclusion, mastitis facilitated the absorption of cefquinome from the mammary gland of lactating goats and induced marked changes in milk pH, emphasizing the importance of performing pharmacokinetic studies of antimicrobial agents in infected animals.  相似文献   
100.
The objective was to assess the influence of pomegranate seed oil supplementation on the quality of fresh, cooled and frozen–thawed Arabian breed stallion semen. Eight stallions (n = 4 per group) received their normal diet (control group) or normal diet top dressed with 200 ml of pomegranate seed oil (PSO group). Semen was collected every fifteen days for 90 days. Stallions were reversed across the treatments after a sixty‐day interval. In cooled and stored condition (2, 12 and 24 hr), spermatozoa motion characteristics, membrane integrity, viability, morphology and lipid peroxidation were analysed. In frozen–thawed semen, sperm dynamic characteristics were analysed by CASA, acrosome status and mitochondrial activity (evaluated by Flow cytometry) determined. The effects of treatment, time, semen type and their interactions were submitted to PROCMIX (SAS®), and means compared by the Tukey test. Also, collected semen samples were artificially inseminated to evaluate fertility and pregnancy rate after day 60 of the experiment. The results from fresh condition showed that semen volume, sperm concentration, abnormality and live sperm were not affected by dietary treatment (p > 0.05). In cooled condition, the higher value for sperm plasma membrane integrity and viability was observed in PSO group compared to control after 24 hr cooled and stored in 5°C. In postthawed condition, the higher value for CASA total motility and acrosome status was observed in PSO group compared to control group (p < 0.05). One hundred and twenty‐six mares were artificially inseminated for fertility trial using control and PSO groups’ fresh semen. The average pregnancy rates were not significantly different between control and treated group (62.88% and 65.90%, respectively) (p > 0.05). We concluded that under the conditions of this study, dietary supplementation of 200 ml pomegranate seed oil seems to relatively improved Arabian horse sperm quality during storage in cooled and frozen condition via increasing plasma membrane integrity, viability and acrosome status, but did not improve the pregnancy rates.  相似文献   
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